<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
    <title>Title</title>
</head>
<body>
<select class="selector">
    <option value ="volvo"selected>Volvo</option>
    <option value ="saab">Saab</option>
    <option value="opel" >Opel</option>
    <option value="audi">Audi</option>
</select>
<a href="#" onclick="choose()">选中</a>
</body>
<script>
    function choose(){
        console.log($(".selector").val())
    }
</script>
</html>